Self-lubricating piston.



S. F, ARBUCKU-IL SELF LUBRICATING PSTON. APPLICATION FILED FEB. 26.1918.

Patented Feb. l1, 1919.

seiiinnn r. ARBUGKLE, or Inninunronrs, inniana.

SELF-LUBRICATING PISTGN.

parts.

The object of this invention is the auto-4 matic lubrication oi' thepacking of the piston in a cylinder, adapted particularly for utilizingor pumping air or gas so that the device will never leak and have at alltimes its maximum power and eiiicieiicy.

To the foregoing end, one feature of the linvention consists incombining with a leather or otherpacling for a piston, of a lubricating'chamber in the piston for con taining oil or lubricating` material incontact with the paclring so that it will be conveyed by capillaryattraction to the surfaces ot" the packing which engages the cylinder,.and thus maintain an air or gas tight joint, an'dalso keep the metal orother packing in ,i goed condition so as to contribute to its long life.This lubricating chamber may be made by merely utilizing a hollowpiston, as herein shown. There may alsobe an oil cup secured to thepiston rod and communicating with said oil chamber in the piston bymeansl of a conduit piston rod.

Another feature of the invention consists in combining with the piston,a disk of leather or other packing material, the annular edge portion ofwhich is bent over and around the piston for furnishing the surface toengage the cylinderl and by inaking said surface relatively lide so asto obtain a wide bearing surface and thereby avoid the evil effects orwearing action resulting from jarring or vibration of the devicewhile`in operation.

The full nature of the invention will be understood from theaccompanying drawu ings and the` following description and claims:

ln the drawings, Figure l is a. central lon-v gitudinal section of acylinder and piston including my invention. Fig. 2 is a centrallongitudinal section of a inodilied form. Fig. 3 is a .similar sectionof still another modied form.

There is shown herein a cylinder 10 pro- Specification of Letters atent.Paqgmlygd Figli, if 1919 Application filed February' 26, 1918.

Serial lilo. 2l9,208.

vided with nicans ll at one end for connecting an air or gas conduit.The other end ci' the cylinder is open and internally threaded toreceive a cap l2. A piston rod 13 operates through this cap. The cap hasanair vent 1&1- in it.

nissi'rl The inner portion ci the piston rod is i duced to leave a.shoulder 15. u{UnftliefV reduced portion a cup-shaped 'pistoifl lisplaced, beingl of somewhat smaller diameter than the cylinder. @ver theopen end of this cupshaped piston member a leather washer or diskpacking 17 fits, its diameter being greatl enough for its peripheralportion to be bent back over and around the periphery of the piston andlit tightly between the piston and cylinder.. A metal washer 18 is thenplaced on the piston rod against the packing-17 and it is tifrliteneddown by a nut 19. This washer should be oi. about the saine diameter asthe piston so as to clamp and hold securely the packing between 'thepiston and the washer.

It is seen. that this construction leaves a chamber 20 so that thepiston isa hollow piston and has in it a chamber for holding oil orlubricating` material in a relatively large quantity and in directcontact with the body of the packing. The oil will, of course, bycapillary attraction, permeate all parts of the packing and keep itmoist and in goed condition.

rlChis construction. enables suoli a pistonto be used a very long time`without any atten tion to its lubrication. Ordinarily the lubrication.isplaced in. the piston while it is assembled and then left there unlessall used, but if desired, a further supply of lubricating,l 'materialmay. be furnishedby means or an oil cup 21 secured on the piston rod andprovided with a conduit 22 lead ing 'from the oil cup longitudinally ofthe piston rod and opening' into the chamber 2O in the.piston. `Withthis arrangement it becomes unnecessary to disassemble the device inorder to charge the piston with oil as it may be supplied at intervals4through the oil cup 2l and conduit 22.

ln the incdilied form shown in Fig. 2, the packing is shown. turned overthe washer in stead of the hollow piston. This is where the pistonpushes instead of pulls. The principle, so far as lubrication isconcerned, however, is the saine.

The inodiriied forni shown in Fig. 3 re verses the construction shown inFig. ,win

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order to enable the device to be worked in the same situation as in Fig.2. In other words, in Fig. 3 the hollow piston 16 is on the inner end ofthe piston rod and the washer is next to the shoulder 15 in said rod.The packing is clamped between them in exactly the same fashion as inFig. l, but reversed.

It isv seen from the foregoing that such a cylinder and piston may bemade air or gas tight and may be lubricated automatically by ltilling4the chamber .in the piston with lubricating material in immediatecontact with the body of the packing.

The invention claimed is 1. A piston rod one end thereof being reducedin diameter to form a shoulder, a cup-shaped piston member on saidreduced end with one side open and the opposite side engagino saidshoulder, a disk-shaped packing member on said rod and closing theopening in said piston member, and a washer on the piston rod ofsubstantially the same diameter as the hollow piston member and onthe\opposite side of the packing foi-,pressing the packing against theperipheral edge of said piston.

2. A piston rod, a cup-shaped piston member on said rodV with one sideopen, a diskshaped packing member on said rod and closing the opening insaid piston member and with its peripheral portion overlapping andsurrounding said. piston member, anda washer on the piston rod ofsubstantially the same diameter as said hollow piston member forclamping the packing tightly against said piston member. I

3. A piston rod, a cup-shaped piston member on said rod with one sideopen, a diskits inner end reduced and threaded and ,pro-

vided with a shoulder, a pistonformed of a hollow member open on oneside, a washer of substantially the same diameter "as the piston, and apacking disk between the hollow member and the washer, all three of saidlast-mentioned elements being on the reduced portion of the piston rod,and a nutl on the inner end of the pist-011 rod for clamping said pistonthereon .against the shoulder.

5. A cylinder, a piston rod, a hollow piston on said rod havingafchamber for lubrieatingmaterial, and a packingdisk closing one side ofthe hollow member and having its peripheral' edge overlapping andsurrounding said piston,- said piston rod 'being provided with alongitudinal conduit in it extending outside Vof the cylinder andcommunicating with' the lubricating chamber and the piston whereby saidchamber may be supplied with lubricating material externally of thecylinder.

In witnegs whereof l have hereunto al'lixed my signature.

SAMUEL F. ARBUCKLE.

